I bought one because uncoated lead bullets were all I could to reload for quite some time. It's been deeply unreliable due to the tightness of the chamber and now that coated lead bullets are available again, I've gone back to shooting the stock Glock barrel.
Spending another $30 to make it "usable" -- especially when so many others are experiencing the same issues -- feels like a ripoff. And yes, I wish I'd bought KKM.
Which makes me happy that they didn't charge me (or the other person who reported sending their barrel back on this thread). I spent $5 to ship it to them and they just fixed it. Though I did do like was suggested, write a detailed letter with just a little disgust
That said, I have no problems with their chambers being tight. I'd much rather they be that than so sloppy they fit well out of spec rounds. At least with a tight chamber you have somewhere to go.